P2CB4 code meaning
Charge Air Cooler Coolant Pump B Supply Voltage Circuit
Powertrain system Generic code P2Cxx codes Check engine light
What P2CB4 means
P2CB4 concerns the power feed of charge air cooler pump B rather than its command line: the pump finds its supply missing or outside the window in which it can run. No manufacturer documents P2CB4 publicly. Ford's 2024 gasoline OBD summary contains the same fault type, 1C (supply out of range), for auxiliary coolant pump B (P2B62); it is monitored all the time from 11 V battery voltage and logged after 5 s. Because the pump electronics sit inside the housing, as Bosch describes for its PCE pump, the pump measures its own supply pin and reports the result. A blown fuse, a relay with burnt contacts, a corroded ground, a damp plug or a weak battery are the usual causes; a voltage-drop test with the pump running finds hidden resistance. Without power the pump stops.
P2CB4 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyEasy, DIY possible
- Typical labor0.3 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2CB4
- MIL on
- Pump B silent, charge air temperature climbs
- Other supply-related codes may be stored at the same time
Common causes of P2CB4
- Most likelyBlown fuse or faulty relay in the pump B feed
- PossibleCorroded or loose ground connection of the pump
- PossibleMoisture or corrosion at the supply pins of the connector
- Less likelyWeak battery or charging fault pulling the voltage down
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Cac coolant pump bWiring harnessECM
What each part of P2CB4 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| C | Area: hybrid propulsion. |
| B4 | The exact fault in that area. |
What to do next
- Note P2CB4 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2CB4
What does P2CB4 mean?
P2CB4 means "Charge Air Cooler Coolant Pump B Supply Voltage Circuit". P2CB4 concerns the power feed of charge air cooler pump B rather than its command line: the pump finds its supply missing or outside the window in which it can run. It is a generic code, so it means the same on every make.
Is it safe to drive with P2CB4?
Drive gently and only to a workshop. With P2CB4 the car can go into limp mode (reduced power) to protect itself.
Will P2CB4 fail an emissions test?
Yes, it can. P2CB4 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2CB4 to fix?
Difficulty: easy. A typical repair takes 0.3 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2CB4 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.